Liquid fuel burner apparatus



June 25,1940., E. l. KRABER 2,205,983

LIQUID FUEL BRNBR APPARATUS Filed Hav. 9, 1939 Y Patented `lune `25, 1940 PATENT OFFICE 2,205,983 LIQUID FUEL nomma APPARATUS Edwin I. Kraber, York, Pa., assigner to York Oil n Burner Co., Inc., York, Pa., acorporation of Delaware Application November 9, 1939, Serial' No. 303,697 s claims. A(el. s-f2s)l fuel pipeI'I near its forward end may be sup- This invention relates to liquid fuel burner apparatus, and more particularly to the arrangement of and support for electric ignition leads positioned within a controlled air supply conduit or passage. The holder or support is particularly adapted for use in cooperation with air iiow controlling devices of the iris diaphragm type, as shown, for example, in the patent to James D. Lalor #2,037,663, granted April 14, 1936.

Liquid fuel burners of the spray type having an oil pipe and nozzle arranged centrally within a surrounding combustion yair supply conduit are known.. The use of electric spark ignition at acter described which results in minimum in terference with a controlled flow of combustion air through such a supply conduit.

It is the further objectof this invention toprovide an ignition lead insulating support of small size adapted to be positioned on and carried by a fuel supply pipe where the pipe and ignition leads pass through an iris type air valve.

A further object is the provision of an insulating support of the character described the surfaces of which assure ample creepage distances for minimizing leakage or surface discharge of the high tension ignition current between the leads and the pipe, or between the leads and adjacent air valve devices. Other objects and advantages of this invention will be apparent from the following description of the embodiment of the invention illustrated in the accompanying drawing in which:

Figure 1 is a plan view, partly in section, rof the furnace end of a spray or gun type liquid fuel burner having an ignition lead support constructed in accordance with my invention.

Figure 2 is an elevation view, partly in section, of a portion of the apparatus shown in Figure 1.

Figure 3 is a sectional view on line 3--3 of Figure 1.

Referring to Figure 1 of the drawing, the fuel nozzle of a liquid fuel burner device is indicated by the numeral I0. The nozzle I0 is at the furnace end of a fuel supply pipe I I, the latter being centrally arranged and supported within an air supply conduit or tube I2. The air conduit I2 is connected by coupling anges I3 and I4 to the outlet I5 of an air blower or fan not shown. The

ported centrally, within the air conduit I2 by a stationary air spiral or spider device I 6 havingv feathered arms I1 to impart any desired whirling motion to the forced air supply as it approaches the burner nozzle.

An adjustable iri`s diaphragm I8 is provided for controlling the character and volume of air constructions shown in the drawing and in the above mentioned Lalor patent are examples of satisfactory air control devices.`

' An electric spark gap for ignition purposes is indicated by the numeral 2 I. High tension current is conducted to the gap by a pair of metal leads or bussbars 22. The leads 22 maybe supported Aadjacent the spark gap by a pair of insulating bushings 23 of porcelain or the like secured in or to the arms or blades I'l of the spider` I6. 'Ihe central ignition lead holder or support is indicated by the numeral 24 and is formed of porcelain or other insulating material.

'Ihe holder 24 extends through the diaphragm opening andiis positioned on the fuel pipe II,

which latter extends through thecentral bore lines in Figure 1, to increase the creepage distance between the entrance of the lead 22 into the outer surface of the holder 24 and the contact of the holder with the fuel pipe II. Sufficient creepa'ge distance, usually two or more inches, may thus be provided ina short holder to avoid loss or discharge of the high tension currentfrom the leads to the fuel pipe.- The iris diaphragm I8 is preferably arranged so that it cannot be closed' enough-"to contact with the possibility of creepage loss between the leads 22 and the diaphragm segments is also avoided.

In the operation of spray type liquid fuel burners of the character shown, a smooth flow of combustion-supporting air to the air spiral or blades il increases the burner eillciency and di-v minishes losses due to excessive air agitation and pressure fluctuations in the supply conduit. The use of the iris type diaphragm to control air ow diminishes air stratification and agitation, and restricts the size of the air passage evenly on all sides, as distinguished from the effect of vane or gate type air valves. The novel ignition lead holder herein described has been found to aid in avoiding excessive air agitation and pressure fluctuation because its air-how or streamline contour has minimum disturbing action on the smooth flow of air through the restricted iris openingA surrounding the holder. 'I'he holder described may be relatively short and still provides adequate insulation for the high tension leads, because of its counterhored ends and its spacing from the air valve parts.

It is vto be understood that this invention is also applicable to liquid fuel burners of other types, such, for instance, as pan, tray and retort burners.

Other advantages of my improved apparatus will be readilyapparent from the above description thereof. Obviously, variations in the nature and arrangement of the elements described will be evident to those skilled in this art, and this invention contemplates any equivalent structure within the scope of the following claims.

Having described my invention, what I claim and desire to secure by Letters Patent is:

1. In liquid fuel burner apparatus, the combination comprising, an air supply conduit, an iris diaphragm valve in said conduit for regulating the air flow therethrough, a fuel supply pipe supported within said conduit and passing through said valve, electric ignition leads within said conduit, an insulating holder for said ignition leads supported on said pipe and extending through said valve, said holder having a relatively smooth outer surface to Aminimize interference with the flow of air through said conduit under control of said diaphragm valve.

2. In liquid fuel burner apparatus, the com bination comprising, an air supply conduit, an iris diaphragm valve in said conduit for regulating the air flow therethrough, a fuel supply pipe supported within said conduit and passing through said valve, electric ignition leadswithin said conduit, an insulating holder for said ignition leads supported on said pipe and extending through said valve, said holder being formed of refractory insulating material and having a relatively smooth outer surface tapering inwardly toward the ends to provide a streamline contour for minimizing interference with the flow of air through said conduit under the control of said diaphragm valve.

3. In liquid fuel burner apparatus, the com.

bination comprising, an air supply conduit, an iris diaphragm valve in said conduit for regulating the air flow therethrough, a fuel supply pipe supported within said conduit and passing through said valve, electric ignition leads within said conduit, an insulating holder for said ignition leads supported on said pipe and extending through said valve, said holder being formed of'insulating material and having counterbored ends of a diameter greater than the outer diameter of the fuel supply pipe to provide added creepage distance between the'ignition leads and the fuel supply pipe, said holder having a smooth outer surface of streamline contour for minimizing interference with the flow of air through said conduit under the control of said diaphragm valve.

4. In liquid fuel burner apparatus, the combination comprising, an air supply conduit, an iris diaphragm valve in said conduit for regulating the air flow therethrough, a fuel supply pipe supported within said conduit and passing through said valve, electric ignition leads Within said conduit, an insulating holder for said ignition leads supported on said pipe vand extending through said valve, said holder having a central axial bore for said fuel supply pipe and having longitudinal passages on opposite sides of said central bore for said ignition leads, the outer surface of said holder being substantially smooth and with oppositely tapered ends to provide streamline contour for minimizing interference with the ow of air through said conduit under the control of said diaphragm valve.

5. In liquid fuel burner apparatus, the combination comprising, an air supply conduit, an

iris diaphragm valve in said conduit for regulating the air flow therethrough, a fuel supply pipe supported within said conduit and passing .through said valve, electric ignition leads within said conduit, an insulating holder for said ignition leads supported on said pipe and extending through said valve, said holder being approximately oval in cross-section Where it extends through said valve and having a relatively smooth outer surface to minimize interference with the flow of air through said conduit under control of said diaphragm valve. A

6. In liquid fuel burner apparatus, the combination comprising, an air supply conduit, a diaphragm valve positioned in said conduit for controlling the air now therethrough, a fuel supply pipe supported within said conduit and passing through said diaphragm valve, electric ignition leads'within said conduit, an insulating holder for said ignition leads supported on said pipe and extending through said diaphragm valve, said holder having a relatively smooth outer surface to minimize interference with the flow of air through said conduit under control of said diaphragm valve.

EDWIN I. KRABER. 

